﻿#region Copyright & License
/* Copyright 2001-2005 (C) Lilly Corporation.  All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:

- Redistributions of source code must retain the above copyright
notice, this list of conditions and the following disclaimer.

- Neither the name of the PixVillage Team, nor the names of its
contributors may be used to endorse or promote products
derived from this software without specific prior written 
permission. 

THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 
COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES INCLUDING,
BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 
LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 
CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 
LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 
ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 
POSSIBILITY OF SUCH DAMAGE.
*/
#endregion


using System;
using System.Reflection;
using System.IO;
using System.Xml.Serialization;
using System.Collections;
using System.Collections.Generic;
using System.Text;

using EAI.Logging;

namespace EAI.Config
{
    /// <summary>
    /// The sigleton configuration manager instance for configurations.
    /// </summary>
    public class ConfigurationManager
    {
        /// <summary>
        /// The hash table to stores all the config entities from xml files.
        /// </summary>
        private static readonly Hashtable hashTable = new Hashtable();

        /// <summary>
        /// The singleton instances.
        /// </summary>
        public static readonly ConfigurationManager Instance = new ConfigurationManager();

        /// <summary>
        /// Hiden the class constructure.
        /// </summary>
        private ConfigurationManager()
        {
        }
        
        /// <summary>
        /// Clears all the config entites stored in hashtable.
        /// And the configuration manager with create and new instance when application vias it.
        /// </summary>
        public void FlushAll()
        {
            hashTable.Clear();
        }

        /// <summary>
        /// Clears the specify type config entity.
        /// </summary>
        /// <typeparam name="T">The specify type derivated from config base class.</typeparam>
        public void Flush<T>()
        {
            Flush<T>(string.Empty);
        }

        /// <summary>
        /// Clears the specify type config entity.
        /// </summary>
        /// <typeparam name="T">The specify type derivated from config base class.</typeparam>
        public void Flush<T>(string extensionKey)
        {
            hashTable[typeof(T) + extensionKey] = null;
        }

        /// <summary>
        /// Gets the config entity base on specify type.
        /// </summary>
        /// <typeparam name="T">The config entity type.</typeparam>
        /// <param name="isFlush">True or flase to indicates whether need flush data.</param>
        /// <returns></returns>
        public T GetConfig<T>(bool isFlush) where T : ConfigBase
        {
            return GetConfig<T>(isFlush, string.Empty);
        }
        
        /// <summary>
        /// Gets the config entity base on specify type.
        /// </summary>
        /// <typeparam name="T">The config entity type.</typeparam>
        /// <param name="isFlush">True or flase to indicates whether need flush data.</param>
        /// <returns></returns>
        public T GetConfig<T>(bool isFlush, string category) where T : ConfigBase
        {
            T xmlObj = null;
            try
            {
                string hashKey = typeof(T) + category;
                xmlObj = hashTable[hashKey] as T;

                if (xmlObj == null || isFlush)
                {
                    T instance = Activator.CreateInstance(typeof(T)) as T;
                    instance.Category = category;
                    xmlObj = instance.GetConfig() as T;

                    hashTable[hashKey] = xmlObj;
                }

            }
            catch (Exception ex)
            {
                Log4NetHelper.GetLogger().Error(ex.Message, ex);
            }

            return xmlObj;
        }

        /// <summary>
        /// Saves the config entity to xml files.
        /// </summary>
        /// <param name="configObj">The config entity.</param>
        public void PersistentConfig(ConfigBase configObj)
        {
            if (configObj != null)
            {
                configObj.PersistentConfig();
            }
        }
    }
}
